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991.
992.
Multiparametric human hepatocellular carcinoma characterization and therapy response evaluation by hyperpolarized 13C MRSI 下载免费PDF全文
Stephan Düwel Markus Durst Concetta V. Gringeri Yvonne Kosanke Claudia Gross Martin A. Janich Axel Haase Steffen J. Glaser Markus Schwaiger Rolf F. Schulte Rickmer Braren Marion I. Menzel 《NMR in biomedicine》2016,29(7):952-960
Individual tumor characterization and treatment response monitoring based on current medical imaging methods remain challenging. This work investigates hyperpolarized 13 C compounds in an orthotopic rat hepatocellular carcinoma (HCC) model system before and after transcatheter arterial embolization (TAE). HCC ranks amongst the top six most common cancer types in humans and accounts for one‐third of cancer‐related deaths worldwide. Early therapy response monitoring could aid in the development of personalized therapy approaches and novel therapeutic concepts. Measurements with selectively 13 C ‐labeled and hyperpolarized urea, pyruvate and fumarate were performed in tumor‐bearing rats before and after TAE. Two‐dimensional, slice‐selective MRSI was used to obtain spatially resolved maps of tumor perfusion, cell energy metabolic conversion rates and necrosis, which were additionally correlated with immunohistochemistry. All three injected compounds, taken together with their respective metabolites, exhibited similar signal distributions. TAE induced a decrease in blood flow into the tumor and thus a decrease in tumor to muscle and tumor to liver ratios of urea, pyruvate and its metabolites, alanine and lactate, whereas conversion rates remained stable or increased on TAE in tumor, muscle and liver tissue. Conversion from fumarate to malate successfully indicated individual levels of necrosis, and global malate signals after TAE suggested the washout of fumarase or malate itself on necrosis. This study presents a combination of three 13 C compounds as novel candidate biomarkers for a comprehensive characterization of genetically and molecularly diverse HCC using hyperpolarized MRSI, enabling the simultaneous detection of differences in tumor perfusion, metabolism and necrosis. If, as in this study, bolus dynamics are not required and qualitative perfusion information is sufficient, the desired information could be extracted from hyperpolarized fumarate and pyruvate alone, acquired at higher fields with better spectral separation. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
993.
Lactobacillus crispatus strain SJ‐3C‐US induces human dendritic cells (DCs) maturation and confers an anti‐inflammatory phenotype to DCs 下载免费PDF全文
Solat Eslami Jamshid Hadjati Elahe Motevaseli Reza Mirzaei Samad Farashi Bonab Bita Ansaripour Mohammad Reza Khoramizadeh 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(8):697-710
Lactobacillus crispatus is one of the most predominant species in the healthy vagina microbiota. Nevertheless, the interactions between this commensal bacterium and the immune system are largely unknown. Given the importance of the dendritic cells (DCs) in the regulation of the immunity, this study was performed to elucidate the influence of vaginal isolated L. crispatus SJ‐3C‐US from healthy Iranian women on DCs, either directly by exposure of DCs to ultraviolet‐inactivated (UVI) and heat‐killed (HK) L. crispatus SJ‐3C‐US or indirectly to its cell‐free supernatant (CFS), and the outcomes of immune response. In this work we showed that L. crispatus SJ‐3C‐US induced strong dose‐dependent activation of dendritic cells and production of high levels of IL‐10, whereas IL‐12p70 production was induced at low level in an inverse dose‐dependent manner. This stimulation skewed T cells polarization toward CD4+ CD25+ FOXP3+ Treg cells and production of IL‐10 in a dose‐dependent manner in mixed leukocyte reaction (MLR) test. The mode of bacterial inactivation did not affect the DCs activation pattern, upon encounter with L. crispatus SJ‐3C‐US. Moreover, while DCs stimulated with CFS showed moderate phenotypic maturation and IL‐10 production, it failed to skew T cells polarization toward CD4+ CD25+ FOXP3+ regulatory T cells (Treg) and production of IL‐10. This study showed that L. crispatus SJ‐3C‐US confers an anti‐inflammatory phenotype to DCs through up‐regulation of anti‐inflammatory/regulatory IL‐10 cytokine production and induction of CD4+ CD25+ FOXP3+ T cells at optimal dosage. Our findings suggest that L. crispatus SJ‐3C‐US could be a potent candidate as protective probiotic against human immune‐mediated pathologies, such as chronic inflammation, vaginitis or pelvic inflammatory disease (PID). 相似文献
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995.
《Seminars in immunology》2016,28(3):241-249
C3 glomerulopathy (C3G) describes a spectrum of glomerular diseases defined by shared renal biopsy pathology: a predominance of C3 deposition on immunofluorescence with electron microscopy permitting disease sub-classification. Complement dysregulation underlies the observed pathology, a causal relationship that is supported by well described studies of genetic and acquired drivers of disease. In this article, we provide an overview of the features of C3G, including a discussion of disease definition and a review of the causal role of complement. We discuss molecular markers of disease and how biomarkers are informing our evolving understanding of underlying pathology. Research advances are laying the foundation for complement inhibition as a targeted approach to treatment of C3G. 相似文献
996.
Mikael Laredo Victor Waldmann Paul Khairy Stanley Nattel 《The Canadian journal of cardiology》2018,34(11):1396-1406
The incidence of atrial fibrillation (AF), the most common sustained arrhythmia and a major public health burden, increases exponentially with age. However, mechanisms underlying this long-recognized association remain incompletely understood. Experimental and human studies have demonstrated the involvement of aging in several arrhythmogenic processes, including atrial electrical and structural remodelling, disturbed calcium homeostasis, and enhanced atrial ectopic activity/increased vulnerability to re-entry induction. Given this wide range of putative mechanisms, the task of delineating the specific effects of aging responsible for AF promotion is not simple, as aging is itself associated with increasing prevalence of a host of AF-predisposing conditions, including heart failure, coronary artery disease, and hypertension. Although we usually think of old age promoting AF, there is also evidence that young age may actually have a protective effect against AF occurrence. For example, the low AF incidence among populations of young patients with significant structural congenital heart disease and substantial atrial enlargement/remodelling suggests that younger age might protect against fibrillation in the diseased atrium; efforts at understating how younger age may prevent AF might be helpful in elucidating missing mechanistic links between AF and age. The goal of this paper is to review the epidemiologic and pathophysiologic evidence regarding mechanisms underlying age-related AF. Although the therapeutic options for AF have recently improved, major gaps still remain and a better understanding of the special relationship between age and AF may be important for the identification of new targets for therapeutic innovation. 相似文献
997.
The discovery of new and more potent chloropyramine (C4) analogues for the potential treatment of invasive breast cancer 下载免费PDF全文
《Chemical biology & drug design》2018,91(1):314-321
Breast cancer is the second most common cancer worldwide, accounting for 25% of all female cancers. Although the survival rate has increased significantly in the past few decades, patients who develop secondary site metastasis as well as those diagnosed with triple negative breast cancer still represent a real unmet medical challenge. Previous studies have shown that chloropyramine ( C4 ) inhibits FAK‐VEGFR3 signalling. More recently, C4 is reported to have SASH1 inducing properties. However, C4 exerts its antitumour and antiangiogenic effects at high micromolar concentrations (>100 μm ) that would not be compatible with further drug development against invasive breast cancer driven by FAK signalling. In this study, molecular modelling guided structural modifications have been introduced to the chloropyramine C4 scaffold to improve its activity in breast cancer cell lines. Seventeen compounds were designed and synthesized, and their antiproliferative activity was evaluated against three human breast cancer lines (MDA‐MB‐231, BT474 and T47D). Compound 5c was identified to display an average activity of IC50 = 23.5–31.3 μm , which represents a significant improvement of C4 activity in the same assay model. Molecular modelling and pharmacokinetic studies provided more promising insights into the mechanistic features of this new series. 相似文献
998.
Ying-Hui Dai An-Dong Wang Yu-Lin Chen Ming-Yu Xia Xin-Yi Shao Dong-Chun Liu 《Journal of Asian natural products research》2018,20(6):581-585
A new indole alkaloid N′-formylserotonin (1), along with five known indole alkaloids N′-methylserotonin (2), 5-hydroxy-1H-indole-3-carbaldehyde (3), N-acetylserotonin (4), 6-hydroxy-1-oxo-3,4-dihydro-β-carboline (5), and bufoserotoin C (6), were isolated from the water extract of traditional Chinese medicine Chansu. Their structures were elucidated on the basis of spectral analyses. The cytotoxicities of 1–6 against human lung adenocarcinoma epithelial cells A549 were tested using the MTT method. Compound 6 exhibited stronger cytotoxic effect than 5-FU, and 1–5 showed no cytotoxic effects. Bufoserotonin C is one of the cytotoxic components in water-soluble extract of Chansu. 相似文献
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